Abstract:

Biological nanocomposites such as nacre, bone and wood synergistically combine strength, stiffness and toughness with lightweight structure, whereas most man-made engineering materials with higher densities follow the rule-of-mixtures, according to which strength and toughness are mutually exclusive properties. Biomimetic approaches study and mimic nature’s concepts and material structures with the aim of developing high-performance bioinspired materials. Recent studies have shown that many of the properties of natural nanocomposites arise from their hierarchical structures from multiple length scales. Molecular level control and design are known to be crucial for the performance of the natural materials especially at the interfaces of the softer matrix and the harder reinforcing elements.

In this work, examples of biopolymer matrices were studied from the mechanical perspective in order to understand how biological components, such as genetically engineered proteins and graphene flakes, could be used to design an organic matrix at the molecular level and to control its macroscopic material properties. The results indicated that the biopolymer networks can be functionalized non-covalently in aqueous and mild conditions directly via self-assembly in order to influence the mechanical properties.